Causes, Symptoms of Lung Atelectasis & its Diagnosis
Lung Atelectasis happens when a lung or its lobe partly or fully gives away (collapses) as a result of the shrinkage of the alveoli, which are the tiny air sacs, inside the lung. Lung atelectasis is a usual difficulty that affects the respiratory system after a major surgery.
Lung atelectasis is also an impediment that could occur due to other issues affecting the respiratory system such as cystic fibrosis, foreign objects breathed into the lungs, tumors in the lung, immune weakness in the respiratory system and injuries to the chest.
In this article we will read about the causes of lung atelectasis, symptoms, risk factors, complications and tests to diagnose lung atelectasis.
Causes of Lung Atelectasis
Lung atelectasis may be caused due to a blocked airway (obstructive) or external pressure on the lungs (non-obstructive). Lung atelectasis affects almost everyone who has had surgery due to anesthesia. Anesthesia changes how one breathes on a normal basis and how gas is absorbed. The interference with the pressure may result in some level of collapse of the alveoli in the lungs. This condition mostly occurs after heart bypass surgery.
Obstructive lung atelectasis may result from the following:
- Mucus plug can cause obstructive lung atelectasis. When mucus accumulates in the airways during and after surgery because of the inability to cough, lung atelectasis can occur. During surgery, one is given drugs that may result in a partial inflation of the lungs such that normal secretions accumulate in the airways. These secretions clear after suctioning that is done after surgery. This does not always work through and they may continue to build up. Mucus plugs affect asthmatic people as well, children and people affected by cystic fibrosis.
- Foreign bodies can cause lung atelectasis. When children inhale foreign objects such as a peanut or a small toy, lung atelectasis can occur.
- Narrowing of major airways from a disease can cause obstructive lung atelectasis. Major airways can be constricted and scarred by infections such as tuberculosis and fungal infections can cause lung atelectasis.
- Tumors affecting a major airway may cause lung atelectasis. A tumor can constrict the airway causing lung atelectasis.
- Blood clot can lead to lung atelectasis. A blood clot can occur when there is a notable amount of bleeding in the lungs and the victim is unable to cough it out resulting in lung atelectasis.
Non-obstructive lung atelectasis may be caused by:
- Injury can cause non obstructive lung atelectasis. An accident that affects the chest could make the victim resist taking deep breaths because of the pain and thus cause the lungs to be compressed leading to lung atelectasis.
- Pleura effusion will cause non obstructive lung atelectasis. This occurs when fluid builds up between the inside of the chest wall and the tissues lining up the lungs.
- Pneumonia can cause non obstructive lung atelectasis. Pneumonia infects the lungs and this may cause non obstructive lung atelectasis temporarily.
- Pneumothorax can lead to non-obstructive lung atelectasis. This is a condition that occurs when air gets into the space between the lungs and the chest wall resulting in the partial or full collapse of the lung.
- Scars in the lung tissue can cause non obstructive lung atelectasis: this could be due to injury to the lung, infection or surgery.
- Lung tumors can cause lung atelectasis. If the tumor is large, it can put pressure on the lung and deflate it instead of blocking the air passages.
Symptoms of Lung Atelectasis
Lung atelectasis does not show signs that are clear. If one has symptoms of lung atelectasis, they may include:
- Dyspnea which is labored or difficulty in breathing.
- Tachypnea where a person takes more breaths per minute than normal.
Lung atelectasis condition mostly occurs when one is already in hospital but it is advisable to seek medical attention in case of difficulties with breathing in order to get an accurate diagnosis and immediate treatment. Emergency care should be sort immediately breathing becomes increasingly difficult.
Risk Factors for Lung Atelectasis
There are several risk factors for lung atelectasis. They include:
- Age is a major risk factor for lung atelectasis. People who are older than 60 years and children younger than 3 years are at a higher risk.
- Conditions that affect and obstruct spontaneous yawning, coughing, and sighing.
- Lack of movement due to being restrained on a bed is a risk factor for lung atelectasis.
- Problems with swallowing especially in senior citizens. This results in secretions into the lung which could cause infections.
- Diseases affecting the lungs such as asthma, COPD, cystic fibrosis are potential risk factors for lung atelectasis.
- Preterm birth is a risk factor for lung atelectasis.
- Recent surgery involving the abdomen and chest is a major risk factor for lung atelectasis.
- Being under general anesthesia recently.
- Weakness in the respiratory muscles due to injury involving the spinal cord or muscular dystrophy.
- Drawing minimal breath into the lungs due to medication, pain or other limitations are also the risk factors for lung atelectasis.
Complications for Lung Atelectasis
The following complications result due to lung atelectasis:
- Hypoxemia is a complication of lung atelectasis. Lung atelectasis interferes with the patients lungs and does not allow oxygen to alveoli.
- Lung atelectasis could cause pneumonia as the mucus in the fallen lung may result in an infection.
- Lung atelectasis can be life threatening in a baby or a person already affected by lung disease especially were one loses the entire lung or a lobe.
Tests to Diagnose Lung Atelectasis
The medical practitioner may conduct a series of tests to diagnose lung atelectasis and unmask the cause. These tests are as follows:
- Chest X-ray- a chest X-ray can identify a foreign object in the lungs of children or adults.
- CT scan- a CT scan is more effective because it can measure the volumes in all the lungs or just a part of them. It can also show whether the collapse was as a result of a tumor which the X-ray is incapable of doing.
- Oximetry for lung atelectasis. This involves measuring the oxygen saturation in the blood using a small device that is placed on the finger of the patient.
- Bronchoscopy for lung atelectasis. The visual examination of the bronchus using an instrument called a bronchoscope. The doctor can also remove blockages to the airway such as mucus plug or foreign bodies.